Whole wings of the hospital were moved to large underground shelters.

"How many people know about the underground shelter at the church?"

The machine was not really built to pan around a dark, underground shelter.

Night or day, it made no difference down in the underground shelter.

"Most of us have already gone into our underground shelters."

The church is bigger than it's ever been, and the underground shelter won't be much of a secret for long.

All that is, but two who were protected in an underground shelter.

Everyone must have been huddled around the television in the underground shelter.

We had to go to school in underground shelters.

These were used as underground shelter during both world wars.